Process of burning lime



(No Model.) 7

JOSEPH 8v JOHN. DRUEUKER.

PROCESS OF BURNING LIME.- No. 358,437. Patented Mar. 1', 1887.

ing fed with a warm blast.

UNITED STATES PATENT OFFICE.

JOSEPH DRUECKER, orron'r WASHINGTON, WISCONSIN, AND JOHN DBUEOKER, OF CHICAGO, ILLINOIS.

PROCESS OF BURNING LI'ME.

SPECIFICATION forming part of Letters Patent No. 358,437, dated March 1, 1887. I

Application filed November 19, 1886. 7 Serial No. 219,393. (No model.)

To all whom it may concern:

Be it known that we, JOSEPH DRUEOKER, a citizen of the United States, residing at Port Washington, in the county of Ozaukee and State of Wisconsin, and JOHN DRUECKER, a citizen of the U .iHed States, residing in Ohicago, in the county of'Cook and State of Illinois, have invented a new and useful Improvement in Processes of Burning Lime, &c., of which the following is a specification.

Our invention relates to an improved method of burning lime, cement, &c.

The object of the inventiouis to cheapen the process, and we accomplish it as follows: The hot air heretofore allowed to escape from the top of the kiln we conduct back to the where it mixes with fresh air and warms the latter, so that the draft is continually be- VVe also employ, by preference, mechanical means to quicken the speed of the draft. If the returned hot air contains smoke or unconsumed gases, no harnris done to the stone, data, being treated, nor does any harm result from the changed character of the blast, as wetind by actual use of the invention. The tests made by us demonstrate that nearly double the ordinary product can be turned out, with the use of even less than the ordinary amount of fuel in a given time, by our process.

We have illustrated in the drawings the best form now known to us of apparatus designed for the working of our process in connection with an ordinary limekiln; but of course we do not wish to be limited to any special construction of apparatus.

Figure 1 of said drawings is a vertical section of the kiln, and Fig. 2 a horizontal Section thereof on line 2 2 of Fig. 1.

In said drawings, A represents the walls of the customary form of a continuously-operating limekiln, B the feed-door, and G the discharge-opening, thereof. I

D is the fire-chamber, and E the ash-pit under the grate (I. There may be two of these firechambers.

F is a hinged cover for the top of the kiln, which may be opened partly or wholly by the rope f.

The stone to be treated is fed into the main chamber a, and the flame and heat of the fire pass through it to the top of the kiln.

G is a pipe leading from the upper portion of chamber a, as indicated, to the ash pit or pits E, and H is a fan placed in said pipe and acting to create a downward current therein. It results from this construction that the hot air from the top of the kiln is drawn back to the fires, and as it issues into the ash-pit it mixes with the fresh air admitted therein through the openings 0, thus changing and greatly increasing the temperature of the air by which the fire is supported. The blast produced by the fan also results incidentally in quickening the draft and the consequent action of the fires. Some of the products of combustion will escape from under the cover F, but the downward suction of the draft will draw the major portion of them to the fire. The acceleration of the draft increases its strength also, and the material being burned is at all times surrounded by arapidly-changing current drawing off forcibly all exhalationsfrom the material, and as the draft naturally seeks the more open and direct channels between the stone the added strength caused by the fan draws the air from the closer and more obstructed portions, thus securing perfect work in all parts of the chamber.

Of course the nature, as well as the temperature and speed of the air-blast, is very considerably modified by our invention; but our use of the process has demonstrated that the quality of the product of the kiln is not affected thereby unless it be-in the direction of improvement.

' An important advantage attending this working of our process lies in the fact that the amount of work done is rendered inde pendent of the weather. All experienced limekiln-operators understand that in damp weather a kiln will not produce as much as in dry Weather, but under our invention the dampness in the air is prevented from affecting the result.

ing lime, &c,, consisting in drawing the hot air, &c., from the top of the kiln and forcing it back to the fire by means of a blast, substantially as set forth.

JOSEPH DRUEGKER. JOHN DRUEOKER.

\Vitnesses to the signature of Joseph Druecker:

JOHN C. SCHROELING, WM. H. LANDOLT. Witnesses to the signature of John Drnecker:

H. M. MUNDAY, EDW. S. EVARTS. 

